Stereotype plate casting device



March 25,1941. w HUCK 2,236,212

STEREOTYPE PLATE CASTING DEVICE Filed'DecL' 4; i957- s Sheets-Sheet .1

INVENTOR- March 25, 1941-. w. F. HUCK STEREOTYPE PLATE CASTING DEVIQE Filed D96 4, 1937 Shootg-Sheut 2 INVENTOR. wqawk glQ wyv;

March 25, 1941. w. F. HUCK 2,236,212

STEREOTYPE PLATE CASTING DEYICE Filed Dec. 4, 1937 3 Sheets-Sheet 3 V i w I p 2/ W2.

Patented Mar. 25, 1941 UNITED STATES STEREOTYPE PLATE CASTING DEVICE William F. Huck, Richmond mu, N. Y., assignor to R. Hoe a 00., Inc., New York, N. Y., a corporation of New York Application December 4; 1937, Serial No. 178,131

14Claims.

This invention relates to plate casting mechanism and more particularly to such mechanism wherein a closed mould is provided for casting plates under pressure and improved means is provided to force the molten metal into the mould. In the use of closed moulds in plate casting, it is desirable that the molten metal be heated to the required temperature before forcing it into the. mould, and that this temperature be maintained until the mould is completely filled. It is also desirable that the metal be maintained under constant pressure after being forced into the mould until it has solidified, and that excess metal be permitted to flow back from the mould. Provision to permit the escape of air and dross is also requisite.

One of the principal objects of this invention is to provide a plate casting mechanism embodying in its structure efllcient and durable means whereby the above desiderata will be obtained.

v Another object is to provide in a plate casting mechanism a closable electrically heated mould and an electrically driven pump operable to force molten metal into the mould.

Still another object is-to provide means to maintain the molten metal under pressure in the mould until the same has solidified and then to permit excess molten metal to be automatically removed from the mould.

by-pass valve whereby the pressure on the metal will be constant until the same has solidified and by which the excess metal will be directed back to the melting pot.

A still further object is to provide a novel form of'vent valve whereby air is permitted to escape from the spout, metallic dross will be trapped, and

'- when the mould is filled this entrapped dross and excess metal will be released and flow back into 40 the melting pot.

Another object is to provide a plate casting mechanism of generally improved construction, whereby the device will be simple, durable and inexpensive in construction, as well as convenient, practical, serviceable and efficient in its use.

With the foregoing and other objects in view,

which will appear as the description proceeds, the

invention resides in the combination and arrangement of parts, and in the details of construction hereinafter described and claimed.

The preferred embodiment of the invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a side view of a plate casting mechanism embodying the features of this invention;

Figure 2 is a view similar to Figure l, but with A further object is to provide a novel form of I the mould parts in section and showing these part in closed mould position;

Figure 3 is an enlarged section through the intake portion of the mould and showing a valve controlled vent;

Figure 4, 5 and .6 are sectional views through a valve controlling the outlet flow of metal from a pump and showing theseveral positions of the parts thereof during its operation; Figure 7 is an enlarged section through the intake portion of a somewhat modified form of valve controlled vent, dross trap. and excess metal release-arrangement; and I Figure 8 is an electrical wiring diagram for the controls of the mould and pump operating motors.

The plate casting mechanism illustrated in the drawings is especially adapted to insure that the plates will be of uniform density throughout. While the casting mould shown is especially adapted for casting flat stereotype plates, it will be understood that the form of the mouldmay be altered for casting curved plates and still include the features of the invention. This mechanism is provided with closable mould parts, the interior of which. is in connection with an electrically driven pump immersed in molten metal. The connecting spout between the pump and the mould is, heated to prevent the metal from cooling as it flows therethrough. A vent is provided in the connecting spout to permit the escape of dross and airfrom the same and which is closable by means of an automatically r, pressure operated valve, An outlet valve is provided at the pump to control the flow of metal therefrom and to assist in maintaining constant pressure on the metal in the mould until it has solidified; and to permit excess metal to flow back to the melting potwhen the pressure is relieved whereby no appreciable tail pieceis left connected to the casting.

Referring now to Figures land 2 of the drawings, a metal melting pot ii in which a pump l2, preferably of the rotary gear type, is disposed, constitutes the receptacle in which the metal to be used is held and maintainedin the proper molten condition. The pump [2 is supported within the pot I l upon the end of a tubular member l3 through which the operative parts thereof are connected to an electric motor M by a shaft (not shown). The motor i4 is mounted upon a rear bracket or frame member i 5 extending from one side of a standard It.

'I'he'mould is constituted by upper and lower parts i1 and I8 respectively, the upper part i'l being pivoted between the bracket l5 and a simiiar front bracke'tor frame member I! and the lower. part pivoted, to the standard.

' in suchi'a manner that the mould parts I] and?" are adapted to be together intoclosely. en-

' gaging relationship. A hand lever-2i upon a shaft; 22 to rockthe-sam'e, actuates. themould parts I1 and I3 to swing them together; see Figure 1 2, or apart, see Figure 1, by means of an arm 23 secured to the shaft 22 and connected by a link 23 to the mould part II, and an arm 23 secured to the shaft 22 and connected by a link 23 to the mould part l1, The end of the link 26 is connected to eccentric portion 21 on a shaft 23 journaled in a lug 29 on the mould part II. When desired an electric motor Ill may be provided to drive a crank disc I02 which is drivingly connected to an arm 103 secured to the shaft 22 by a link I. The crank disc I32 is mounted on a shaft I 03 and is arranged to be driven by a pinion I36 secured on the shaft of the motor IOI.

A lever 3|, secured to the shaft 23, is connected by a link 32 to a hand lever 33 secured to a shaft 34 journaled in the brackets I5 and I3. The shaft 34 i formed with eccentric portions 35 on which the upper mould part is pivoted. A quadrant plate 36 formed as an extension of the bracket I5 is provided with spaced apart openings 31 through which a bolt 38 passes to secure the hand lever 33 and the shaft 35. The arrangement of the levers 3|, 33, link 32, and eccentric portions of the shafts 28 and 34 is such that, when it is desired to cast plates of different thickness, the hand lever 33 is adjusted and clamped by the bolt 38 to the plate 36 in the proper position to locate the upper and lower mould parts I! and [8 in position relatively to each other to tightly close upon a gauge frame 39 disposed between the mould parts and secured to the face H of the part ll. The gauge frame 39 may be interchanged with others in accordance with the thickness of the plate to be cast and is arranged to hold a matrix 32 against the face ll of the mould part II.

The mould part ll is preferably hollow, the interior chamber 43 being connected with the face 4! by a plurality of openings 44 and with a suitable vacuum pump by a port 45, whereby the matrix 42 is maintained tightly against the face 4| due to the vacuum established in the chamber 43. The lower mould part 13 may have provision for holding a backing paper 46 upon the face 41 thereof, herein consisting of rolls l8 and a clamp plate 43. The part I8 is also hollow, the chamber 3| being in connection with a supply of cooling fluid by inlet and outlet ports 52 and 53. The usual valves (not shown) are provided to control the supply of cooling fluid to the mould part l3 to cool the casting after the same is made.

A spout or duct containing member 34 is secured to the standard IS in position to have the outlet 55 of the duct 56 therein; correspond to the opening between the mould parts l1 and it when they are in closed position (see Figures 2 and 3). The spout 53 extends between the brackets l5 and I9 and has an upper surface I! which the upper mould part II thmugh the gauge frame 33 tightly engages, and a beveled surface 53 which the lower mould part l3 engages upon a correspondingly beveled surface 53. Closely adjacent the outlet of the duct 36, a vent 3| is provided. A pressure ball closing valve 32 is disposed in the vent 3| and which is normally retained in vent opening position by gravity. Molten metal under pressure flowing upwardly through the duct It will cause the air therein to-escape. cut'oi amsescapefromi' Suitable M are i in'the. walls"ofthe 3puutf I the duct l3. to that Y the moltenrnetal 'is not cooled before-z-it enters the and" that it does not solidify with'theplate.

The duct 33 is connected to the'p'ump 12 by a conduit 65 through the open front end of a'valve cylinder 33, said open front end of the cylinder 33 constituting an inlet port. A valve plunger or piston head 61 is disposed in the cylinder it. The plunger 61 has a rearwardly extending shank 33 guided by and through a cylinder end 63. The interior of the cylinder is in connection with the casing of the pump l2 at its open front end, or inlet port, the front wall II having a valve seat 12 formed therein to agree with the form on the adjacent end of the plunger 61. A spring 13 disposed in the cylinder 38 reacts against the piston head 81 and the cylinder end 33 to constantly urge the plunger forwardly into closed position upon the seat I2. The plunger 61 is acted upon by the pressure of the molten metal from the pump l2 to unseat it and force it rearwardly against the urge of the spring 13 whereby it opens an outlet port 14 (see Figure 5), connected to the conduit 63 whereupon the metal flows through the latter into the duct 56 and thence to the mould. When the mould and duct become completely fllled with metal the increased pressure developed by the pump l2 causes the plunger 61 to retract further rearwardly against the action of the spring 13 and open a' port 15 (see Figure 6), leading from the cylinder interior into the melting pot H whereupon excess metal escapes into the pot H and the pressure upon the metal in the duct and therefore upon the mould is maintained uniform and constant. The term port as used herein is to be understood to deflne a part, or portion,of the cylinder 65 having a bore extending therethrough. I

During the period that the mould is full and under pressure, cooling fluid is circulated through the chamber ii in the lower mould part It and as soon as the casting metal has solidified, the pump 12 is stopped and the plunger 61 seats on the valve seat I2 closing the opening into the pump. Unsolidifled metal still remaining in the conduit 63 and duct 53, flows downwardly, through the Port ll, through the cylinder 36 in back of the piston head 31 and into the pot H through the port 13, thus clearing from the solidified cast plate in the cooled mould, substantially all excess metal. By maintaining the metal in the mould under constant and uniform pressure, a plate is cast which is substantially of uniform density throughout. The provision of the novel by-pass valve whereby the excess metal is drained from the spout, saves, not only metal, but time in removing surplus metal from the cast plate.

The arrangement shown in Figure 7 permits the escape of air from the duct leading to the mould and includes means to entrap metallic dross and to insure its escape with excess metal after the mould is filled. while maintaining the metal in the mould under a constant pressure. The spout or duct containing member 3|, illustrated in Figure 7, is secured to the standard It in position to have the outlet 32 of the duct 33 therein, correspond to the opening between the mould parts l1 and I3 when they are in closed position as shown. The spout 3! extends between the brackets I8 and I8 and has an upper surface 88 which the gauge frame 88 tightly en a es. and a beveled surface which the lower mould part I8 engages upon the corresponding beveled surface 58.

Closely adjacent the outlet. 82 the spout 8| is provided with an upwardly extending cavity 88 from which a port 81 extends to the surface 88. Another port 88 is provided in the spout 8I extending from the surface 88 adjacent the port 81 into-connection with a duct 88, which is directed rearwardly with its mouth 8I overlying the melting pot II. A casing 82 having a recas 88, which extends over both the ports 81 and 88 to connect the same, is mounted upon the surface 88 of the spout 8|. The casing 82 is provided with a bore 98 which is in alignment with the port 81 and in which a valve member 88 is slidably mounted. The valve member 88 is adapted to close the port 81, being constantly urged against the surface 88 by a. spring 88 reacting against the member 88 and a plug 81 threadingly mounted in the upper portion of the bore 88 and by which the tension on the spring 86 may be adjusted. The spring 96 is disposed about a stem 88 provided upon the valve member 88 and which is slidingly mounted in the plug 81. The valve member 88 is provided with a vent groove 88 which, when the valve member is in port closing position, connects the port 81 with the duct 88 through the recess 88 and port 88.

By the provision of the vent groove 88, air is permitted to escape from the duct 88 through the port 81, and metallic dross collects and is entrappedln the cavity 88 insuring that only clean metal will be forced into the mould. After the mould is filled, the increased pressure built up by the continued action of the pump I2 will force the dross against the valve member 88 raising it, by compressing the spring 86, to open the port 81 wherebythe dross and excess metal will escape through the ports 81 and 88 into the duct 88 and thence to the melting pot II while a constant pressure will be maintained on the metal in the mould as it is being cooled. By this arrangement, the valve cylinder 88, with its associated parts, may be omitted and the plate casting mechanism of this invention will be further simplified without affecting its efficiency. I

When the mould operating motor MI is used to open and close the mould by means of the crank disc I82, the arm I88 and the link I88, it may be electrically interlockedwith the pump motor I8 in accordance with the control circuits shown in Figure 8. As herein shown, theaction of the motors I8 and I 8| is substantially automatic for the cycle of operations; in the casting of a plate. The operation is started by pressing a normallyopen push button I 81 to close a circuit (to a switch controlling solenoid III) that may be traced from a main line conductorl88, by

conductor I88 to one terminal of the push button I81, thence from'the other terminal of the push button I81 through conductor II2, to one terminal of an interlock switch Il8, the other terminal of the switch II8 beingconnected by a conductor II8 to one terminal of the, solenoid III, The other terminal of the solenoid III is connected by a conductor II8 to the other main line conductor IIB. v

The solenoid III thus energized closes a circuit between the terminals of a switch II1, one of which is connected to the conductor I88 by a conductor H8 and the other being connected to one terminal of the mould'm'otorIlII byacon-.

- opened and the motor I8 stops.

ductor III. The other terminal of the motor MI is connected by a conductor I2I to the main line conductor III. Energization of the motor "I rotates the crank disc I82 to. close the mould.

Connected to the shaft III of the crank disc I82 to which the push button I 81 is connected. As soon as the motor I8I starts, the cam I28 re-.

leases the switch I28 to close the circuit, wherebythe solenoid I I I is maintained energized until the mould is closed, whereupon the cam I28 opens the switch I28 and the motor I8I stops.

As soon as the mould is closed and the motor IN is stopped, a cam I28, provided on the cam disc I28 closes a switch I88 to complete a circuit through a conductor I82 from the conductor I88 and through a conductor I8I to one terminal of a motor I88 of a suitable timing controller, the other terminal of which motor is connected by a conductor I88 to the main line conductor Ill. The motor I88 through reduction gears I88 rotates a pair of switch controlling cam discs I88 and I81 mounted on the shaft I88. The cam disc I88 is provided with a cam surface I88 adapted to close a switch I H and to maintain it closed a predetermined interval of time to energize a switch controlling solenoid I82. The switch I has one of its terminals connected by a con- II) conductor I28 to the terminal of the solenoid III ductor m to the main line conductor m and its other terminal connected to one terminal of the,

cuit between the terminals of a. switch I88, one

of which is connected to the conductor I88 and 1 the other of which is connected by a conductor I81 to a terminal of the pump motor I8. The other terminal of the motor I8 is connected by a conductor I88 to the main line conductor I88 through the conductor I88. Energization of the motor I8 actuates the pump to fill the closed mould with casting metal and this operation continues until the camming surface I88 passes the switch I which then opens to de-energize the solenoid I82 whereupon the switch I88 is The solenoid I82also controls the interlock switch 8' which is in closed position when the solenoid I82 is de-energized and open when the solenoid is energized, and the switch I88, controlling the pump' motor, is closed. The switch H8 is in the circuit of a switch I88 controlled" one terminal of the switch II8 through the conductor I I2 by a conductor I82, the other terminal of the switch I I8 being connected by a conductor II8 to the conductor I28 connected to one terminal of the switch I28. The other terminal ofthe switch I88isconnected by conductors I88 and I88 to the main line conductor I88.

energized to start the mould motor I8I to open the mould and this operation is continued after Upon closing of the switch I88, the solenoid III is the cam ISI passes the switch I49, and allows it to reopen, due to the cam lug I25 permitting release of the switch I28 to maintain the solenoid III energized until the cam lug I24 again opens the switch I26.

The action of the switch I49 is similar to the action of the push button II" in that it is only in operation a sufllcient amount of time to insure the closing of the switch I26. The motor I33 is maintained energized a suflicient length of time to insure the opening of the switch I by the release of the same from the action of the lug ISI, and also to set the timing motor Ill in position for its next starting operation, to close the switch Ill by the continued action of the cam I29. The interlock switch Ill prevents the possible operation of the motor IOI to open the mould, while the pump motor I l is operating. From the above, it will be obvious that a control system is provided for the motors I4 and IIII whereby the casting operation may be substantially automatic, requiring only the attention of the operator to initially start it by means of the push button I01.

The various cam discs I23, I24 and I36, III are arranged to provide the proper time intervals for the successive operations. For instance, the switch I28 maintains the motor IOI energized until the mould is closed, the cam I2 9 then starts the timing motor I33 and maintains it energized until the metal in the mould is cooled and the cam discs I36 and I3! are reset in their start position. The disc I" maintains the pump motor ll energized a length of time sumcient to fill the mould with metal, and the disc Il'l closes the mould motor circuit to start opening of the mould and holds it closed until the switch I! closes the maintaining circuit for the motor.

It will be understood that the invention may be embodied in other specific formswithout departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, and it will be further understood that each and every novel feature and combination present in or possessed by the mechanism herein disclosed forms a part of the invention included in this application.

What I claim is:

1. A valve for use in a plate casting mechanism to control the flow of metal to the plate mould thereof, including a hollow casing having an inlet port in one end, a first outlet port spaced from the inlet port end of the casing and at one side thereof, and a second outlet port spaced from the first outlet port and further away from the inlet port end of the casing and at the other side thereof, a valve plunger having an inlet port clomg end slidably mounted in the casing and being of proper length to open the first outlet port into communication through the casing with the second outlet port when in position to close the inlet port, and a spring acting on the plunger to normally hold it in inlet port closing position, the plunger being movable in the casing by pressure imposed against its inlet closing end, to open said inlet port and the first outlet port into communication through the casing.

2. A valve for use in a plate casting mechanism to control the flow of metal to the plate mould thereof, including a hollow casing having a series of three ports spaced apart lengthwise thereof, a spring pressed plunger slidable in the casing and normally closing the first of the said ports and being of such length as to partly open the second of theports into communication with the third of the ports through the casing when the plunger closes the first port, the length of the plunger being suificient to block communication between the second and third ports when the plunger is moved awayfrom the first port to open it and the second port into communication through the casing, the phmger being movable further in the casing to open the third port into communication through the casing with the first and second ports.

3. In a stereotype p ate'casting machine, the combination with a molten metal supply and a mold. of a conduit communicating the mold with the molten metal supply. a member having a dross receiving cavity, formed therein and communicating with the conduit and the atmosphere adjacent the mold, a valve movable responsive to molten metal pressure for interrupting communication between the vent cavity and the atmosphere, and means for forcing molten metal under pressure through the conduit into the mold to fill it, the metal dross and air escaping through the vent cavity until the valve is moved to interrupt communication between the vent cavity and the atmosphere by continuation of :flaigd molten metal pressure after the mold is 4. In a stereotype plate casting machine, the combination with a molten metal 811991! and a mold, of a conduit communicating the mold with the molten metal supply. a member having a dross receiving vent cavity formed therein and communicating with the conduit and the atmosphere adjacent the mold, a valve normally closed to interrupt communication between the vent cavity and the atmosphere andmovable to open position responsive to molten metal pressure, and means for forcing molten metal under pressurefromthemetalsupplythrough theconduit into the mold, the force of the molten metal opening the valve whereby air is forced through the vent cavity to the atmosphere and metal drossvi andexcessmetalaredischarg edfromsaid ca ty.

5. In a stereotype plate casting machine, the combination with a molten metal supply and a mold. of a conduit communicating the mold with the molten metal supply, a member having a dross receiving vent cavity communicating with the conduit adjacent the mold, a return duct communicable with the said cavity and leading therefrom to a location to discharge to the atmosphere and into the molten metal supply, a valve normally biased to closed position to interrupt communication between the vent cavity and the return'duct and movable to open position responsive to molten metal pressure. and means for forcing molten metal under pressure from the metal supply through the conduit into the mold, the force of the molten metal opening the valve whereby air is forced to the atmosphere and metal dross and excess metal are discharged through the vent cavity and return duct back to the molten metal supply.

6. In a stereotype plate casting machine, the combination with a molten metal supply and a mold, of a conduit communicating the mold with the molten metal supply. a member having a dross receiving vent cavity communicating with the conduit adjacent the mold, a return duct communicable with the said cavity and leading therefrom to a location to discharge to the atmom I mo'sphere and into the molten metal supply, a valve normally biased to closed position to interrupt communication between the vent cavity and the return ductand movable to open position responsive tomolten metal pressure, a'

groove formed in the valve t'o'constant-ly communicate the vent cavity with the atmosphere, and means for forcing molten metal under pressure from the metal supply through the conduit into the mold, the force of the molten metal to each mold member at a point spaced from v the said pivotalsupport whereby it I may be moved to open and close the mold, thepivotal support andspaced supporting member for one mold member being provided with eccentrically movable components operably secured to the said mold member whereby the space between the first and second mold members may be varied by the movement of the said movable components to cast plates of different thickness between the mold members, means for operably connecting the eccentrically movable components for simultaneously adjusting them so that the first and second mold members remain in parallelism during the said adjustment, and means to secure the eccentric components inany selected position.

8. In a stereotype plate casting machine, a molten metal supply, a mold having separate mold members, means for pivotally supporting each mold member for independent swinging movement toward and away from the other mold member, a fixed member having a conduit communicating with the molten metal supply, means for moving the mold members about their pivots to and from engagement with the fixed member, mold engaging surfaces formed on the fixed member, a surface formed on each mold member to engage a mold engaging surface of the fixed member when the mold members are moved to engagement with each other and the fixed member whereby the separate mold members and fixed member form a mold cavity with which the conduit communicates, and means for forcing molten metal from the molten metal supply through the conduit into the mold cavity.

9. In a stereotype plate casting machine, the combination with a molten metal supply and a mold, of a valve casing communicable with the metal supply to receive molten metal within the casing, a conduit communicable with the valve casingand mold, a valve movable within and accurately engaging the casing to vary the metal-receiving space within the casing and to control communication through the casing between the metal supply and the conduit, the valve being biased to continuously oppose the flow of molten metal from the supply into the casing to thereby exert constant pressure on the metal, means for forcing molten metal under pressure from the metal supply into the casing, the force of the moltenmetal moving the valve against its bias to increase the volume of molten metal within the valve casing and to establish communication between the metal supply and the so that iiows'under pressure into the mold to fill it and to produce pressure 10. In a stereotype plate casting machine; the

with a molten metal supply and a mold, of a valve casing communicable with the metal supply, a conduit communicable with the valve casing and mold, a valve movable within the casing tocontrol communication through the casing between the metal supply and theconduit. the valve being biasedsto oppose the fiow of molten metal from the supply into the casing to thereby exert constant pressure on the metal, a return port formed in the casing and communicahle with the metal supply and controlled by said biased valve,'means for forcing molten metal under pressure from themetal supply into the casing, the force of the molten metal moving the valve against its bias to establish communi cation between the metal supply and the conduit so that metal iiows'under pressure into the mold to fill it, and the continuedfiow of the metal from thesupply after the mold is filled moving the biased valve further into the valve casing against its bias to open the return port so that excess metal is returned therethrough tothe 11. In a stereotype plate casting machine, the v combination with a molten metal supply and a mold, of a valve casing communicable with the metal supply, a conduit communicable with the.

valve casing and mold, a valve movable within the casing to control communication through the casing between the metal supply and the con-- duit, the valve being biased to oppose the flow of molten metal from the supply into the casing to thereby exert constant pressure on the metal, a 1

return port formed in the casing and communicable with the metal supply and controlled by said biased valve, means for forcing molten metal under pressure from the'metal supply into the casing, the force of the molten metal moving the valve against its bias to establish communication between the metal supply and the conduit so that metal flows into the mold to fill it, and the continued flow of the metal from the supply alter the mold is filled moving the biased valve further intothe valve casing'against its bias to open the return port sothat excess metal is returned therethrough to the metal supply, the biased valve returning responsive to the said stress to its initial position when the said metal force is discontinued thereby establishing communication between the conduit and the metal supply through the return port to drain metal from the conduit back into the metal supply.

12. In a. stereotype plate casting machine, the combination with a. molten metal supply and a mold, of a valve casing communicable with the metal supply, a conduit communicable with the valve casing and mold and with the atmosphere at a location adjacent the mold, a normally open vent valve movable responsive to molten metal pressure for interrupting the communication between th conduit and the atmosphere. a valve movable within the casing to control communication between the metal supply and the conduit the conduit so that metal flows into the mold to fill it, the initial flow of the metal towards the mold forcing air past the vent valve to the atmosphere until the mold is filled and then continued flow of the metal from the supply moving the biased valve further into the casing against its bias to open the return port so that excess metal is returned therethrough' to the metal supply.

13. In a stereotype plate casting machine, the combination with a molten metal supply and a mold, of a valve casing communicable with the metal supply to receive molten metal within the casing, a conduit communicable with the valve casing and mold, a return duct communicable with the conduit and leading therefrom to a location to discharge into the molten metal supply, a normally closed yieldable discharge valve for controlling communication between the conduit and the return duct, a valve movable within and accurately engaging the casing to vary the metal-receiving space within the casing and to control communication between the metal supply and the conduit, the valve being biased to continuously oppose the flow of molten metal from the supply into the casing to thereby exert continuous pressure on the metal, means for forcing molten metal under pressure from the metal supply into the valve casing, the force of the metal moving the valve against its bias to increase the volume oi molten metal received within the casing and to establish communication between the metal supply and the conduit so that metal flows into the mold to till it and produce pressure therein, the force of the metal opening the discharge valve to discharge excess metal through the return duct back to the metal supply.

14. In a stereotype plate casting machine, a mold having separate mold members, one mold member being pivotally mounted for swinging movement relative to the other to open and close the mold, supports for the mold members, spaced rotatable members operably supported by the supports, a connecting component supported by and movable with each rotatable member and disposed in eccentric relation therewith, each connecting component being rotatably secured to a mold member so that rotative movement or the rotatable member imparts movement to the mold member, and means for operably connecting the spaced rotatable members so that rotative movement or .one rotatable member simultaneously imparts rotative movement of like amplitude to the other to thereby adiustably move one mold member towards and away from the other in parallelism therewith so that plates of diil'erent thickness may be cast between the separate mold sections.

WILLIAM F. HUCK. 

